1. Field of the Invention
This invention relates to valves and is directed more particularly to a valve responsive to temperature changes of a medium flowing therethrough to modify the rate of flow of the medium therethrough.
2. Description of the Prior Art
In systems, such as refrigeration systems, in which it is important to control the temperature of a liquid flowing into a temperature-sensitive body, such as controlling the temperature of refrigerant entering the evaporator of the refrigeration system, the temperature adjustment means usually is operative in response to a sensed condition in the evaporator indicative of the temperature in the evaporator.
Rather than responding to the temperature of, or in, the evaporator, or other such body, it is deemed beneficial to provide for continuous control of the temperature of the medium entering the body, such that the body is continuously maintained at the most efficient temperature.
Expansion valves have been suggested as a means for controlling the flow of a refrigerant medium into an evaporator of a refrigeration system. An example of such valves is shown in U.S. Pat. No. 2,463,951, issued Mar. 8, 1949 to F. Y. Carter. The Carter valve includes a number of moving parts and is complex and, therefore, expensive.
Other valves of a generally similar nature may be seen in U.S. Pat. No. 3,205,675, issued Sep. 14, 1965 to A. A. Matthies, U.S. Pat. No. 3,405,535, issued Oct. 15, 1968 to A. A. Matthies, and U.S. Pat. No. 3,835,659, issued Sep. 17, 1994 to Lyle E. McBride, Jr.
There exists a need for a valve responsive to the temperature of fluid flowing therethrough to automatically regulate the flow rate of the fluid, to maintain the body to which the fluid is directed at an efficiency optimum temperature, which valve is simple and reliable in construction and inexpensive to obtain and maintain.